Police and the family of missing 62 year old Geoffrey Montgomery are becoming increasingly concerned for his wellbeing.
The north Belfast man was last seen in the outside the Mater Hospital around noon yesterday.
A PSNI spokesman said: "However by this stage he could be anywhere in Belfast as he has a tendency to walk into town from his home in North Belfast and also around local parks.
"Geoffrey’s family are very concerned for his well-being as he does currently require medical treatment and left while undergoing this treatment."
Police are appealing for Geoffrey or anyone who know of his whereabouts to contact officers on 101 quoting reference 751 of 27/09/17.